There are many different possibilities for using lasers to treat an obstructing prostate gland. The laser may be used in a continuous wave or pulsed mode. The wavelength may be well absorbed by the prostatic tissue (such as with KTP or holmium lasers) thereby improving the cutting action; alternatively the wavelength may be poorly absorbed by the prostate (such as with gallium arsenide or neodymium YAG lasers) thereby promoting coagulation. The delivery device may be a simple bare laser fiber used free beam or contact; it may be delivered via a contact tip or diffuser probe; alternatively the laser may be deflected through a right angle via for example a gold-coated fiber. Finally the laser may be delivered via a balloon which is inflated within the prostate. Over 100 patients have been treated. Flow rates and post-micturition residual on ultrasound, PSA, transrectal ultrasound (TRUS) volume were recorded preoperatively on all patients unless in acute retention in which case only the PSA and TRUS volume were performed. Postoperatively these measures were all repeated at 3 and 6 months.
Graham M. Watson,
"Lasers and the prostate: many ways to skin a cat", Proc. SPIE 1879, Lasers in Urology, Gynecology, and General Surgery, (28 May 1993); doi: 10.1117/12.146245; https://doi.org/10.1117/12.146245